1. Field of the Disclosure
The present invention relates to a lighting apparatus, more particularly, to a lighting apparatus that can light a room intensively, fitted to a characteristic of a room, by adjusting an angle of light distribution and that can prevent glare, with improved optical uniformity and beautiful exterior appearance.
2. Discussion of the Related Art
Generally, the lighting industry has a long history which is as old as civilization and it is closely related with human beings.
The lighting industry has been under sustainable development and various studies on light sources, a light-emitting method, a driving module and lighting efficiency improvement have been made.
A light source usually used in a lighting apparatus may be an incandescent lamp, an electric-discharge lamp and a fluorescent lamp and such a light source is used for various purposes such as for domestic usage, landscape usage and industrial usage.
The incandescent lamp which is a resistive light source has disadvantages of deteriorated light-emitting efficiency and a generated heat. The electric-discharge lamp has disadvantages of a high price and a high voltage. The fluorescent lamp has an environmental disadvantage of mercury usage.
To solve those disadvantages of such the light sources, interests in light emitting diodes (LED) have been increasing because they have advantages of high light emitting efficiency, a variety of colors and designable freedom.
Such a light emitting diode (LED) is a semiconductor element which emits a light when a voltage is applied to the light emitting diode forwardly. The light emitting diode has a long life span of usage, low power consumption. In addition, it has electrical, optical and physical properties which are proper to mass production. Because of that, the light emitting diodes (LED) have been substituting for the incandescent lamps and fluorescent lamps rapidly.
Meanwhile, when a LED lighting apparatus is used as a simple lighting apparatus, the directionality of light (for example, a light distribution angle) may be adjusted by using a lens structure such as a condensing lens.
To adjust the directionality of the light, an auxiliary lens structure is required. Accordingly, a manufacturing process of a lighting apparatus might be complex and the manufacturing cost might be rising. Also, it is difficult for the lighting apparatus to be fitted to a characteristic of a lighted room.